Here's paula faris. I'm veronica corningstone. I'm ron burgundy. Go yourself, san diego. Reporter: To avoid the dreaded pink slip it's easy to avoid the obvious slipupses. Obvious to most of us. Great work, everyone. Sharp broadcast. I got to fire you. Reporter: This anchorman, now infamous for the f-bomb had a predictable outcome. Tell us a little about yourself, a.J. Reporter: Oh, I no, he was fired. But while some career killers are crystal clear, the workplace IS RIFE WITH HIDDEN DOs AND DON'Ts. Can a person be completely oblivious that their career is being jeopardized? Oh, all the time. There are lots of different ways. To get fired, and sometimes you'll never know what you did wrong. Reporter: Cynthia shapiro is a former human resources executive. In her tell all book "corporate confidential," she rev secret office no-no's nobody tells you. Often behavior people think is good. You talk about these hidden career landmines in your book. It sounds terrifying. It can be. You just need to know where they are, and so you could avoid them. Let's call them the eight secret sins at the office. Office sin number 8 -- being popular. Being part of the in crowd could put you on the outs. We all want to be popular. How in the world could that be a bad thing? It's a big one. Being popular can erode your job security very quickly. It leads to sharing too much personal information at work. I have sat in meetings where the ceo said, I heard this person is going through a nasty divorce, let's not promote them. Friendships, you know, need to be very strategically crafted. Doesn't sound like much of a friendship. You know, it is more of an alliance. Reporter: Office sin number seven -- multi-tasking. If you pride yourself on typing, talking, calculating and chomping all at the same time, you're not alone. In this economy, you can't afford to take a break. This "saturday night live" skit suggests a bathroom office to allow multitasking. Everywhere. But shapiro says multi-tasking actually makes your performance. Tank. Studies show that dividing your attention between tasks can decrease efficiency and accuracy. Companies say multi-tasking is what they want. It's not really what they want. What they really want you to do is focus in with laser beam focus on one thing and then switch to another and switch to another and switch to another. Reporter: Office sin number 6 talking to human resources. Even though your company will always say it's besto take your troubles to hr that can be an "rx" for trouble. Most people assume that what they tell hr is confidential. All that means is they are not going to blab it to the other employees. But they will absolutely tell your boss. Reporter: So if I am having a problem with my boss -- which i am not -- who do I go to? Well, I would encourage you to figure it out yourself. Reporter: Another office error mistaking your cubicle for your living room. Office sin number 5, over-decorating. Shaprio says you may think it's smart to make your space cozy and comfy but it could really be a career killer. Companies will say, here is your space, you know, this is yours. Reporter: Do with it what you want. Yeah, do whatever you want with it. It's kind of an unconscious test of loyalty and values, because if you fill it with troll dolls and crystals or religious thin, that it's gonna make them feel really, really uncomfortable. Reporter: So you are saying, we shouldn't pimp out the cubicle. It can really work against you very quickly. Reporter: We brought shapiro on a tour of the abc offices, to provide the boss's view of office decor. A really messy office, and a really chaotic office, they would translate that into a chaotic thinker. Reporter: An illuminating tip -- lamps are good. We have the lamps on either side, basically advertising i work late nights. Reporter: Shapiro says family photos can be risky. It's telling the employer that this person would rather be at home with their kids. Reporter: And if you're thinking of bringing your actual children to the office to show them off or tout your family values, shapiro says time-out. Reporter: Office sin number four -- bringing your kids to work. If your kid decides to have a temper tantrum it will reflect on you. If you can't control a child are you gonna manage the company, that kind of thing. So it's, you know, inviting disaster. Reporter: Another recipe for disaster -- bringing in yummy treats for your coworkers. Office sin number three -- feeding others. Wait, what could be wrong with that? This is particularly a mistake for women. Reporter: Dr. Lois frankel, author of "nice girls don't get the corner office," says to be taken seriously, leave the baking to betty crocker. It's a nice thing to do it's not gonna help your career. And if you do it too much, you'll just be seen as the mascot, or the, you know, the, the department mom, and you don't want that. Reporter: Office sin number two -- signing off with love. Adding hugs, kisses, and smiley faces to your emails may seem fun and friendly, but our expert SAYS ICHTS-NAY ON THE XOs. Unless I am emailing somebody that I am very close with they have no place in business correspondence. emoticons completely out. I don't know where thomails are gonna go. Who are they gonna be forwarded to? Smiley faces at the end of emails I am gonna say, save for the people that I am closest to. Reporter: If all these office no-no's make you want to flee the cube, perhaps you should in fact spend more time out of the office. And office sin number one -- working too hard. Burning the midnight oil can actually backfire. Research shows overworking can decrease your performance because it deprives of you sleep and koim pact your image. You're working 24/7, where you're always accessible, where you just kind of seem harried because there's always so much to do, you're not seen as someone who manages their time well. Reporter: So with so many rules, how can work ever feel like anything but a job? How can you even be yourself at the office anymore? Honestly it's easier to be yourself if you know where the land mines are. It's actually very empowering, you can before a guy in a banana suit

This transcript has been automatically generated and may not be 100% accurate.

Career Killers: 7 Secret Sins at Work

Even "good" behaviors can be hidden career killers, experts say.

Twitter Quitters Just Don't Get It

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{"id":19206783,"title":"Don't Work Too Hard: Secret Career Killers","duration":"6:19","description":"A former HR exec's eight office booby traps that could keep you from earning that corner office.","section":"2020","mediaType":"Default"}